test('toBeNull',()=>{
    expect(null).toBeNull();
});

test('void 0->toBeUndefined',()=>{
    expect(void 0).toBeUndefined();
});

test('null->toBeUndefined',()=>{
    expect(null).toBeUndefined();
});

test('null->toBeDefined',()=>{
    expect(null).toBeDefined();
});


test('null->toBeFalsy',()=>{
    expect(null).toBeFalsy();
});

